Axial flow turbine, compressor and the like



July 20, 1948. H. CONS'MTANT ETAL 2,445,661

AXIAL FLOW TURBINES, COMPRESSORS AND THE LIKE Filed Jan. 15, 1944 vINVEN f-S m h dd W iputcnted July 20, 1948 UNITED STATES PATENT OFF!AXIAL FLOW TURBINE, COMPRESSOR AND THE LIKE Application January 13,1944, Serial No. 518,180 In Great Britain September 22, 1941 Section 1,Public Law 690, August 8, 1946 Patent expires September 22, 1961 8Claims.

This invention relates to turbines and other axial flow machines such asrotary compressors wherein the blading is subjected to fluid atrelatively high temperatures as in internal combustion turbine plant. vThe invention specifically relates to the mechanical connecting meansbetween the outer casing and the fixed blade carrying members associatedtherewith on the one hand and the coaxial inner fixed member carryingthe rotor bearing on the otherhand. In operation the temperaturesassumed by these two prtions respectively difief' considerably.

According to the present invention in order to take care of thedifferential expansion due to the temperature diiferences aboveindicated the attachment of the casing of the turbine orthe like to theinner fixed member of the turbine or compressor, which member may be theperiphery of a flexible mechanical support, is through the intermediaryof some or all of the fixed blades, prefably of the first stage of theturbine, which blades at their inner ends or foundation rings" at theseends are provided with radial pegs or pins, preferably integrally, whichengage in radial holes in the inner fixed member aforesaid. Preferablythese pegs or pins are of barrel shape and fit snugly into cylindricalradial holes. With this arrangement freedom for radial expansion ispermitted between the casing and fixed blades carried thereby on the onehand, and the inner fixed member on the other hand, whilst the casing isrigidly located relatively to the inner fixed member in all directionsother than that required for such radial expansion.

The arrangement according to the invention is more'particularly but notexclusively applicable to turbines or the like where the rotor isoverhung from its bearing. It will be appreciated that the first bladestage end of the turbine casing may be directly connected to thedelivery end of an annular combustion chamber, to the remote end ofwhich in axial alignment is connected the compressor which is driven bydirect coupling through an internal shaft from the turbine, the casingof the internal combustion chamber being supported at one end by thecasing of the turbine and at the other end from the casing of thecompressor.

In a convenient arrangement according to a subsidiary feature of theinvention the turbine casing consists of a simple cylindrical outer wallwith an end flange to which is secured such as by set screws one end ofan inner casing wall carrying the fixed blading, and the outlet orannular delivery duct from the turbine, whilst the other end of theinner casing has secured to it ternate rings in segmental form beingfoundation rings carrying the fixed blading of the turbine. It will beappreciated that with this orrangement further flexlbllity in theinterests of thermal expansion in the radial direction for the outercasing is provided. A space for cooling fluid isv preferably providedbetween said inner and outer casing walls.

The single figure or the accompanying drawing is a, half sectionalelevation of part of an internal combustion turbine plant embodying thefeatures of the present invention.

Referring to the drawing, at I is shown the rotor of the turbine inquestion. This rotor is shown as having an integral stub shaft 2 splinedto a sleeve 3 with a flange 8a having a plurality of peripheralperforations 4 for bolting to the main shaft (not shown) extending alongthe axis 5 through the combustion chamber, part of which is generallyindicated at 6, to the air compressor (not shown) supplying saidcombustion chamber, which is of annular form and, as aforesaid, directlyconnects the exhaust of the compressor with the annular inlet member 1of the turbine which-hastthe annular exhaust or delivery passage formedby the tubes 8 and 8. The casing, generally. indicated at ll), of theturbine is connected at the right-hand end with the combustion chamber 6and is connected at the left-hand end with the gas delivery members 8and 8. The

- turbine rotor I carries two rows of blading indicated at H and I2,whilst the turbine casing carries two fixed stages of blading indicatedat I3 and I4, whilst there may be fixed guide blading l5 at the deliveryend: alternatively the illustrated member l5 may be one of a relativelysmall number of radial supporting members uniting the tubular members 8aand 8a to which the members 8 and 8 are welded.

As hereinbefore indicated the turbine casing l8 and fixed blading I3, Il are connected with, and

in fact may be carried by, an internal structure of the plant which isshown as an example as the tubular member I6 extending through thecombustion chamber 6 at least to the air delivery end of the compressor,this arrangement, however, per se forming no part of the presentinvention. The turbine casing Hi, the structure or which is hereinafterdescribed in more detail, is mechanically connected through at leastsome of the blading l3 in the first row, through the flexible dishedmember l1, with the stationary internal member IS. The latter carriesthe fixed race l8 of the turbine rotor bearing H! which is shown as, andpreferably is, of the ball type, the inner race 20 of which is carriedon the sleeve 3 of the turbine rotor. The bearing housing is comprisedperipherally by the inner cylindrical surface of the fixed tubularmember i6, at the right-hand end by an internal flange 2| fixed on, ormay be integral with, the member l6, and at the left-hand end by awasher-shaped member 22 bolted at 23 to the left-hand end of the memberIS. The members 2| and 22 have cylindrical flanges 24 and 25, betweenthe inner surfaces of which and the shaft 2 gas-tight packing of per sewell known form may be provided: and arrangements will be made forlubricating and cooling the bearing I9, which arrangements per se formno part of the present invention. The inner flange of the dish member I1is bolted at 26 to an external flange 21 on the internal stationarymember iii.

The fixed blading l3 of the first row is provided with an innerfoundation ring 28 which has radial pegs or pins 29 according to themain feature of the present invention, which pegs 29 engage in radialholes 30 in the outer peripheral portion of the dished member I1. Thepegs 29 may be provided with helical or other grooves 3| for thereception of cooling air from the jacket of the combustion chamber. Itwill be noticed that there is a slight but appreciable clearance betweenthe outer periphery of the dished member l1 and the inner periphery ofthe foundation ring 28.

The turbine casing l comprises on the one hand the simple cylindricalouter wall 32 (which is a continuation of the combustion chamber outercasing) and the inner wall, hereinafter described, on the other hand.The annular combustion chamber 6 has the outer wall 33 providing, withcasing 32, the outer jacket space 34, and has the inner wall 35providing, with an innermost wall 36, the inner jacket space 3611.Relatively cool air flows in the jacket spaces 34 and 36a as indicatedby the arrows. The lefthand end of the jacket space 34 is divided by anannular partition 31 for directing a good flow of air into the annularspace between the inner and outer walls of the turbine casing.

The tubular exhaust member 8a has secured to its flange 38 on theright-hand side a flanged blade-spacing and gas-guide member 39, and onthe left-hand side a member 43 receiving the left-hand end of theextension of the casing 32. Between the right-hand flange of the member39 and another double-flanged blade-spacing and gas-guide member 4| issecured by bolts 42 the foundation ring 43 carrying the second row offixed turbine blading M. The foundation ring 44 of the first row I3 offixed blading is similarly clamped between the right-hand flange of themember 4| and the flange of the annular inlet member 1, into which theleft-hand ends of the walls 33 and 35 of the combustion chamber extend.

It will be appreciated that an annular space is provided between theinner wall comprised by the built-up members 39 to 44 and member 1, onthe one hand, and the cylindrical outer casing wall 32, on the otherhand, to the right-hand end of which space cooling air can be deliveredfrom the jacket space 34 of the combustion chamber 6. The annular member39 is provided with ducts 45 through which the cooling air can pass intothe delivery passage 8. 9 of the turbine. Circulation of the cool air(or gases) through the aforesaid annular space is maintained by thepressure drop from the inlet of the turbine to its exhaust, and it willbe appreciated that no sealed joint need therefore be made between theannular passage 34 of thecombustion chamber and the annular passagearound the turbine.

We claim:

1. Anaxial fiow machine the blading of which is subjected to fluid atrelatively high temperature comprising an outer casing of the machineand fixed blade-carrying members associated therewith, a fixed member inthe interior of the machine, a ring connecting the inner ends of atleast one row of the fixed blades of the machine, and a mechanicalconnection between said ring and fixed member comprising radial pins onthe inner periphery of said ring, engaging in radial holes in said innerfixed member.

2. A machine as claimed in claim 1, wherein I said pegs or pins are ofbarrel shape and fit snugly into radial cylindrical holes in the innerfixed member.

3. A machine as claimed in claim 1, wherein said fixed member comprisesa flexible member of substantially dished shape.

4. A machine as claimed in claim 1, wherein said fixed member extendsoutwardly toward said ring, and said machine including a blade carryingrotor, and a bearing interposed between said rotor and the inner portionof said fixed member.

5. A machine as claimed in claim 1, wherein a clearance is providedbetween said ring and fixed member for fiow of cooling air therethrough.

6. A machine as claimed in claim 1, wherein said pins are grooved forreception of cooling air, and a clearance is provided between said ringand fixed member for supplying cooling air to the grooves in said pins.

'7. A machine as claimed in claim. 1, wherein a clearance is providedbetween said ring and fixed member for fiow of cooling air therethrough,and including a combustion chamber having walls for directing coolingair to said clearance.

8. An internal combustion turbine plant, comprising an outer casing, aninner wall carrying axially spaced rows of fixed blading, an annulardelivery duct, means connecting said outer casing REFERENCES CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS t'aimber Name Date 1,331,766 Hemingway Feb. 24,1920 1,346,509 olhovsky July 13, 1920 2,080,425 Lysholm May 18, 1937v2282,894 Sheldon May 12, 1942 2,326,072 Seippel Aug. 3, 1943

